The two major problems with the social polarization thesis are its definition and quantification. This article focuses on a dual labour market, locally and internationally, but ignores wider social inequality. A framework developed from Friedmann's world city hypothesis and data on changes in occupation, status and migration are used to test the validity of the hypothesis in Singapore, Hong Kong, Taipei and Seoul. The results show that, in all these cities, there is a common trend towards professionalization, but no accompanying growth in managers, clerks, and self-employed and household labour. Different scenarios of social polarization have been observed in two types of Asian world city, the 'city state' (e.g. Singapore and Hong Kong) and the 'capital city' (e.g. Taipei and Seoul). Singapore and Hong Kong are examples of a centralized development model that enhances the labour force and expands cross-border networks with polarized immigrant workers. In contrast, Taipei and Seoul, both of which are subject to political tensions, demonstrate anti-centralizing tendencies and have had to prevent the emigration of native elites and control the immigration of low-skilled foreign workers. The social polarization hypothesis in Asian world cities needs to be re-examined in the local institutional context mediated by the social policies of developmental states. Resume La these de la polarisation sociale souleve deux grands problemes: sa definition et sa quantification. Cet article s'interesse a un marche du travail dual, sur un plan local et international, en ignorant l'inegalite sociale au sens large. Utilisant un cadre elabore a partir de l'hypothese de la ville mondiale de Friedmann et de donnees sur les evolutions en matiere d'emploi, de position sociale et de migration, il teste la validite de la these a Singapour, Hong Kong, Taipei et Seoul. Toutes ces villes partagent une tendance a la professionnalisation, mais sans augmentation parallele des cadres, des employes de bureau, des travailleurs independants et de la main-d'oeuvre familiale. Des scenarios de polarisation sociale differents ont ete observes dans deux types de villes mondiales asiatiques, l'Etat-cite (comme Singapour et Hong Kong) et la ville-capitale (comme Taipei et Seoul). Singapour et Hong Kong relevent d'un modele de developpement centralise qui ameliore l'emploi et tisse des reseaux transfrontaliers avec des travailleurs immigrants polarises. En revanche, Taipei et Seoul, qui connaissent toutes deux des tensions politiques, presentent des tendances anticentralisatrices et ont du empecher l'emigration de leurs elites locales, tout en controlant l'immigration des travailleurs etrangers peu qualifies. Dans les villes mondiales asiatiques, il convient donc de reexaminer l'hypothese de la polarisation sociale dans le contexte institutionnel local issu des politiques sociales d'Etats promoteurs de developpement.